1. Field of the Invention
The present invention relates to a vehicle seat which protects a head region and a neck region of an occupant at the rear collision.
2. Description of Related Art
Conventionally, when so-called rear collision such as collision during the backing of an automobile or the bumping into the rear region of an automobile occurs, a head region of a seated occupant may suddenly tilt backward due to an inertial movement, and there is some possibility that a neck region receives the impact.
Recently, therefore, various techniques for safely protecting a head region and a neck region of an occupant from the impact at the rear collision have been applied to a vehicle seat of an automobile and the like. One of such techniques is to reduce the impact on the occupant at the collision (e.g., Japanese Patent Application Laid-Open No. 2005-211402).
However, the higher efficiency of reducing the impact is, the more preferable the technique is. Therefore, automobile users desire more efficient absorption of energy at the rear collision to reduce the impact.